Water use in data centers can be a murky issue. Traditionally, water has been used to provide necessary cooling services to data halls by using up excess heat to evaporate the water – much like our bodies do when we sweat. However, this consumes large volumes of water (on the order of millions of gallons per month for modern data centers), making that water inaccessible for other human or natural needs. So, the decision to “burn water” instead of electricity is an important trade-off. Here is a deep dive into the rationale behind this decision, how it is becoming outdated, and why we have made a splash, diving into water-free cooling for our data centers.
Providing cooling services is done at the expense of either electricity or water consumption. In the past, the production of electricity itself often consumed of large amounts of water – typically fossil fuels were burned to evaporate water into steam, which was used to generate electricity. The water used in the generation of electricity is often referred to as “embodied water.” Therefore, a data center cooled by electricity was still responsible for consuming a significant amount of water when that electricity was generated. Whether offsite at electrical plants or onsite at the data center, water consumption was about the same and “came out in the wash.”
The “Belly-Flop” – How this Assumption is Outdated
In the past, this rationale was a reasonable assumption. However, as modern power plants become more water efficient and our electrical grid transitions to renewable power sources (and leading companies make their own faster transitions), there is less water consumed for that electrical generation. Electricity sources like solar and wind power are effectively water-free. Now that there is less embodied water in the electricity, the assumption that embodied water is roughly equal to the onsite consumption of water (for cooling) no longer holds. Ouch.
Understanding that the choice between electricity and water for data center cooling makes a difference in the overall amount of water consumed, we at CyrusOne are leading the way on how to consider data centers’ impact on the world’s water. We are committed to build all of our new facilities without a reliance on water consumption-based cooling. By doing so we are making a splash in the industry; after all, we are making sure there is enough left water to do so.
Stay tuned for our first case study where we took a facility that was using cooling water and transitioned it to water-free cooling and the impact on total water consumed onsite and off.